iTunes...500 songs fitting on 3 CDs sounds about right. Outlook Express...you can save the address book similar to the way you'll save the favorites out of Firefox. Dig around in the options. Once you're done, I'd have them switch to Thunderbird. You will need to look thru every file/folder on the hard drive, because you will loose everything. So any excel files, word docs, pdf's, pictures, videos, emails, anything you want to keep, besides programs that you can just download or reinstall with the disk, needs to be saved either on a disk or a second hard drive. If that turns out to be a lot, you might want to think about getting some DVD disks to put your stuff on, (if you don't have a second hard drive of course). Be careful, double check to make sure you have everything saved somewhere, that you want to keep, before reformatting the hard drive.